<template>
  <el-container class="home-container">
    <!--头部区域-->
    <el-header>
      <div>
        <img src="../assets/heima.png" alt="" />
        <span>电商后台管理系统</span>
      </div>
      <el-button type="info" @click="logout">退出</el-button>
    </el-header>
    <!--页面主体区-->
    <el-container>
      <!--侧边栏区域-->
      <el-aside :width="isCollapse ? '64px':'200px'">
        <div class="toggle-button" @click="toggleCollapse">|||</div>
        <!--侧边栏菜单区-->
        <el-menu
          background-color="#333744"
          text-color="#fff"
          active-text-color="#409eff"
          :unique-opened="true"
          :collapse="isCollapse"
          :collapse-transition="false"
          :router="true"
          :default-active="activePath"
        >
         <!--因为提供的是布尔值所以要加冒号  或者直接unique-opened
        :router="true" 是否使用 vue-router 的模式，启用该模式会在激活导航时以 index 作为 path 进行路由跳转
        default-active当前激活菜单的 index string  每次点击链接都要把对应的地址先保存在sessionStorage中 再取出来动态赋值给default-active-->

          <!--一级菜单-->
          <el-submenu :index="item.id+'' " v-for="item in menulist" :key="item.id">
            <!--要为el-submenu指定唯一的index值，而且index只接收字符串-->
            <!--一级菜单模板区-->
            <template slot="title">
              <!--图标-->
              <i :class="iconsObj[item.id]"></i>
              <!--文本-->
              <span>{{item.authName}}</span>
            </template>

            <!--二级菜单-->
            <el-menu-item :index="'/'+subitem.path+''" v-for="subitem in item.children" :key="subitem.id"  
            @click="saveNavState('/'+subitem.path+'')">
              <!--要为el-submenu指定唯一的index值，而且index只接收字符串-->
              <!--二级菜单模板区-->
              <template slot="title">
                <!--图标-->
                <i class="el-icon-menu"></i>
                <!--文本-->
                <span>{{subitem.authName}}</span>
              </template>

            </el-menu-item>

          </el-submenu>
        </el-menu>
      </el-aside>
      <!--右侧内容主体区域-->
      <el-main>
        <!--路由占位符-->
        <router-view></router-view>
      </el-main>
    </el-container>
  </el-container>
</template>

<script>
export default {
  data(){
    return{
      //左侧菜单数据
      menulist:[],
      iconsObj:{
        '125':'iconfont icon-users',
        '103':'iconfont icon-lock_fill',
        '101':'iconfont icon-shangpin',
        '102':'iconfont icon-danju',
        '145':'iconfont icon-baobiao'
      },
      //是否折叠
      isCollapse:false,
      //被激活的链接地址
      activePath:''
    }
  },
  created(){
    this.getMenuList()
    this.activePath=window.sessionStorage.getItem('activePath')
  },
  methods: {
    logout() {
      window.sessionStorage.clear()
      this.$router.push('/login')
    },
    //获取所有菜单
    async getMenuList(){
    const {data:res}=await this.$http.get('menus')
    if(res.meta.status!==200){
      return this.$message.error(res.meta.msg);     
    }
    this.menulist=res.data
    },
    //点击按钮，切换菜单的折叠与展开
    toggleCollapse(){
    this.isCollapse=!this.isCollapse
    },
    //保存链接的激活状态
    saveNavState(activePath){
      window.sessionStorage.setItem('activePath',activePath)
      this.activePath=activePath
    }
  }
  
}
</script>

<style lang="less" scoped>
.home-container {
  height: 100%;
}
.el-header {
  background-color: #373d41;
  display: flex;
  justify-content: space-between;
  padding-left: 0;
  align-items: center;
  color: #fff;
  font-size: 20px;
  div {
    display: flex;
    align-items: center;
    span {
      margin-left: 15px;
    }
  }
}
.el-aside {
  background-color: #333744;
  .el-menu{
    border-right: none;  //去掉对不齐的效果
  }
}
.el-main {
  background-color: #eaedf1;
}

.el-submenu i{
  margin-right: 10px;
}
.toggle-button {
  background-color: #4a5064;
  font-size: 10px;
  line-height: 24px;
  color: #fff;
  text-align: center;
  letter-spacing: 0.2em;
  cursor: pointer;
}
</style>
